Generator Fault Codes

Briggs & Stratton Generator Fault Codes

Briggs & Stratton's residential standby line — sold as the Home Generator System — doesn't show a digital fault number on a screen the way Generac or Kohler controllers do. Instead it reports trouble through a single fault-indicator LED that blinks a count from one to eight, decoded here as FC_1 through FC_8.

How Briggs & Stratton shows a fault

When the fault-detection system trips, the LED blinks its count, pauses for roughly two seconds, then repeats the same count again for as long as the fault is active — so if you're not sure whether you counted right, just watch it go through the pattern twice. There's no code chart printed on the panel itself, which is why this page exists: match the blink count to the table below and you have the code.

One extra wrinkle worth knowing: if the panel shows a fault condition but the LED itself isn't blinking at all, that typically points to a starting battery so completely discharged it can't even run the indicator — treat that the same way you'd treat FC_1, only more urgently.

Every Briggs & Stratton fault code

CodeMeaningSeverity
FC_1One LED blink: the starting battery's output is below what's needed to crank the engine, so the fault detection system flags a low-battery condition.Medium
FC_2Two LED blinks: the oil pressure switch closed because pressure dropped below roughly the 8 psi range, so the engine shut down to prevent damage. If low oil pressure persists, the unit may start, run for about 20 seconds, then shut down again with this code.High
FC_3Three LED blinks: the generator's output voltage dropped out of the acceptable range, most often tied to a fuel restriction, a wiring problem, or an overloaded generator.Medium
FC_4Four LED blinks: the engine failed to start after repeated attempts.High
FC_5Five LED blinks: the engine ran slower than about 55 Hz for three seconds or more, so the system shut it down to protect connected equipment from low-frequency power.Medium
FC_6Six LED blinks: the engine ran faster than its preset speed limit (the system shuts down immediately if frequency exceeds about 70 Hz), most often from a failed governor.High
FC_7Seven LED blinks: engine oil temperature exceeded roughly 300°F, so the system shut the engine down to prevent damage.High
FC_8Eight LED blinks: the system detected a fault in the transfer switch communication or operation, most commonly a blown fuse in the transfer switch itself.High

Start from the symptom instead

Don't have a blink count yet, or troubleshooting a portable unit with no LED at all? These cut across brands and start from what the generator is actually doing.

What repairs like these typically cost

Battery and charger issues (FC_1) are usually the cheapest fix on this list — often a $200–$500 installed battery replacement. Transfer switch faults (FC_8) and alternator-related voltage faults (FC_3) run higher, since they involve licensed-electrician labor. See the full repair-cost breakdown on the home page for ranges across every fault type, sourced from contractor-rate aggregators rather than a Briggs & Stratton price list.

Before you touch anything.
This site is an independent reference and is not affiliated with, endorsed by, or sponsored by any generator manufacturer. It is not a substitute for a licensed electrician or generator technician. Standby and portable generators involve mains-voltage output and, on LP/NG units, a live fuel-gas supply — work on wiring, the transfer switch, or the fuel system should be done or verified by someone qualified to do it. Pages are written with AI assistance from the sources listed on each page and checked against them before publishing.